Prokaryotes

These flashcards cover key concepts about prokaryotes, including their structure, reproduction, nutrition, and ecological roles.

What are the main differences between prokaryotes and eukaryotes regarding DNA structure?

Prokaryotes have circular DNA, while eukaryotes possess linear DNA found within a nucleus.

What organelles are present in eukaryotes but not in prokaryotes?

Eukaryotes contain organelles, whereas prokaryotes do not.

What type of reproduction do eukaryotes primarily utilize?

Eukaryotes primarily reproduce sexually through the production of gametes.

What are the three basic shapes of bacteria?

Cocci (spherical), Bacilli (rod-shaped), Spirochaetes (spiral).

What is the purpose of flagella in bacteria?

Flagella are used for movement.

How do bacteria exhibit taxis?

Bacteria can sense and respond to stimuli, allowing them to move towards or away from certain conditions.

What are plasmids?

Plasmids are small, circular pieces of DNA that can replicate independently and can move between cells.

What are the main modes of nutrition for prokaryotes?

Prokaryotes can be autotrophs (self-feeders) or heterotrophs (require organic compounds).

What is the difference between obligate aerobes and obligate anaerobes?

Obligate aerobes require oxygen to survive, whereas obligate anaerobes are poisoned by oxygen.

What is genetic recombination in bacteria?

Genetic recombination in bacteria can occur through transformation, transduction, and conjugation.

What is a characteristic of archaea?

Archaea are often found in extreme environments and are thought to be ancient organisms.

What is the role of nitrogen-fixing bacteria?

Nitrogen-fixing bacteria convert nitrogen gas from the atmosphere into a form that plants can use.

What is the significance of endospores in bacteria?

Endospores allow bacteria to survive harsh environmental conditions and can be stimulated by changes in the environment to grow.

What are the effects of exotoxins and endotoxins produced by bacteria?

Exotoxins cause disease symptoms and are secreted by living bacteria, while endotoxins are released when bacteria die and contribute to disease.